Diffusion and Solubility of Hydrogen in Amorphous and Microcrystalline Si:H Films

2001 ◽  
Vol 664 ◽  
Author(s):  
Wolfhard Beyer
Keyword(s):  
Hydrogen Diffusion ◽  
Silicon Films ◽  
Hydrogen Solubility ◽  
Hydrogen Transport ◽  
Microcrystalline Silicon ◽  
Hydrogen Incorporation ◽  
Hydrogenated Amorphous

ABSTRACTHydrogen diffusion and solubility effects in hydrogenated amorphous and microcrystalline silicon films are reviewed. Various diffusion-related effects have been observed which need to be considered in models of hydrogen diffusion. Hydrogen solubility is found to affect hydrogen incorporation and hydrogen transport.

Doping Dependence of Chlorine Incorporation in SiC14-based Microcrystalline Silicon Films

2005 ◽  
Vol 862 ◽  
Author(s):  
Wolfhard Beyer ◽  
Reinhard Carius ◽  
Uwe Zastrow
Keyword(s):  
Fermi Level ◽  
Release Rate ◽  
Hydrogen Diffusion ◽  
Film Growth ◽  
Silicon Films ◽  
Microcrystalline Silicon ◽  
Hydrogen Incorporation ◽  
Doping Dependence

AbstractFor SiCl4-based microcrystalline silicon films the doping dependence of chlorine and hydrogen incorporation was studied. The results reveal a Fermi level dependence with a maximum chlorine (and hydrogen) incorporation for a Fermi level somewhat above midgap. As an explanation, a Fermi level dependence of the chlorine release rate during film growth is considered, similar as valid for hydrogen diffusion and desorption.

STM on doped and undoped hydrogenated amorphous and microcrystalline silicon films

1992 ◽  
Vol 42-44 ◽  
pp. 1398-1402 ◽  
Author(s):  
W. Zimmermann-Edling ◽  
R. Wiesendanger ◽  
F. Finger ◽  
K. Prasad ◽  
A. Shah
Keyword(s):  
Silicon Films ◽  
Microcrystalline Silicon ◽  
Hydrogenated Amorphous

Hydrogen Diffusion in Boron-Doped Hydrogenated Amorphous Silicon Films: Crystallization and Induced Structural Changes

2005 ◽  
Vol 864 ◽  
Author(s):  
F. Kail ◽  
A. Hadjadj ◽  
P. Roca i Cabarrocas
Keyword(s):  
Amorphous Silicon ◽  
Structural Changes ◽  
Hydrogen Diffusion ◽  
Hydrogen Plasma ◽  
Hydrogenated Amorphous Silicon ◽  
Silicon Films ◽  
Hydrogen Atoms ◽  
Boron Doped ◽  
Hydrogenated Amorphous ◽  
Positively Charged

AbstractWe have studied the evolution of the structure of boron-doped hydrogenated amorphous silicon films exposed to a hydrogen plasma. From the early stages of exposure, hydrogen diffuses and forms a thick H-rich subsurface. At longer times, hydrogen plasma leads to the formation of a microcrystalline layer via chemical transport without crystallization of the initial layer. We observe that the hydrogen content increases in the films during a plasma exposure and once the microcrystalline layer is formed hydrogen diffuses out of the sample accompanied with a decrease in the boron content. This effect can be attributed to the electric field developed within the heterojunction a-Si:H/μc-Si:H that drives the positively charged hydrogen atoms in the boron-doped layer towards the μc-Si:H layer.

Isolated Voids in Amorphous Silicon and Related Materials Measured by Effusion of Implanted Helium

2012 ◽  
Vol 1426 ◽  
pp. 341-346 ◽  
Author(s):  
W. Beyer ◽  
W. Hilgers ◽  
D. Lennartz ◽  
F. Pennartz ◽  
P. Prunici
Keyword(s):  
Amorphous Silicon ◽  
Crystalline Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Vacuum Evaporation ◽  
Silicon Films ◽  
Preparation Process ◽  
Hydrogen Incorporation ◽  
Hydrogenated Amorphous ◽  
Deposition Techniques

ABSTRACTEffusion measurements of hydrogen and implanted helium are reported for (undoped) amorphous and crystalline Si:H and related materials. Effusion of helium observed at temperatures > 600°C is attributed to isolated voids present in the material from the preparation process. While rather high void densities are detected for amorphous silicon films prepared by such deposition techniques like vacuum evaporation or sputtering, much smaller densities are found for plasma grown hydrogenated amorphous silicon (a-Si:H). For device-grade a-Si:H, the density of cavities which can trap helium is estimated to be about 2x1018/cm3at most, suggesting that crystalline silicon type divacancies are not the major hydrogen incorporation site.

Effects of Deposition Power and Temperature on the Properties of Heavily Doped Microcrystalline Silicon Films

1996 ◽  
Vol 420 ◽  
Author(s):  
A. M. Miri ◽  
S. G. Chamberlain ◽  
A. Nathan
Keyword(s):  
Substrate Temperature ◽  
Physical Vapor Deposition ◽  
Growth Process ◽  
Film Growth ◽  
Thin Layers ◽  
Silicon Films ◽  
Microcrystalline Silicon ◽  
Hydrogen Incorporation ◽  
Deposition Power ◽  
Heavily Doped

AbstractWe studied the effect of RF deposition power and temperature on the electrical and structural properties of plasma enhanced chemical vapor deposited (PECVD), heavily doped microcrystalline silicon films (n+μC-Si:H). The film growth process was found to be CVDlike at low powers and PVD-like (Physical Vapor Deposition) at high powers. We show that the film properties strongly depend on the nature of the growth process. We observed that at low temperatures the microcrystalline formation is mainly governed by the presence of hydrogen. This can be improved by increasing the substrate temperature. However, a further increase in substrate temperature tends to reduce hydrogen incorporation into the film and hence decreases the role of hydrogen in the formation of microcrystallites. Resistivities as low as 0.1 Ω.cm were achieved for 500Å thin layers deposited at a relatively low temperature of 220°C and power density of 40mW/cm2.

scholarly journals Investigation of the Pressure Dependent Hydrogen Solubility in a Martensitic Stainless Steel Using a Thermal Agile Tubular Autoclave and Thermal Desorption Spectroscopy

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 231
Author(s):  
Patrick Fayek ◽  
Sebastian Esser ◽  
Vanessa Quiroz ◽  
Chong Dae Kim
Keyword(s):  
Stainless Steel ◽  
Thermal Desorption ◽  
Hydrogen Diffusion ◽  
Martensitic Stainless Steel ◽  
Thermal Desorption Spectroscopy ◽  
Hydrogen Uptake ◽  
Hydrogen Solubility ◽  
Automotive Components ◽  
Set Up ◽  
Service Application

Hydrogen is nowadays in focus as an energy carrier that is locally emission free. Especially in combination with fuel-cells, hydrogen offers the possibility of a CO2 neutral mobility, provided that the hydrogen is produced with renewable energy. Structural parts of automotive components are often made of steel, but unfortunately they may show degradation of the mechanical properties when in contact with hydrogen. Under certain service conditions, hydrogen uptake into the applied material can occur. To ensure a safe operation of automotive components, it is therefore necessary to investigate the time, temperature and pressure dependent hydrogen uptake of certain steels, e.g., to deduct suitable testing concepts that also consider a long term service application. To investigate the material dependent hydrogen uptake, a tubular autoclave was set-up. The underlying paper describes the set-up of this autoclave that can be pressurised up to 20 MPa at room temperature and can be heated up to a temperature of 250 °C, due to an externally applied heating sleeve. The second focus of the paper is the investigation of the pressure dependent hydrogen solubility of the martensitic stainless steel 1.4418. The autoclave offers a very fast insertion and exertion of samples and therefore has significant advantages compared to commonly larger autoclaves. Results of hydrogen charging experiments are presented, that were conducted on the Nickel-martensitic stainless steel 1.4418. Cylindrical samples 3 mm in diameter and 10 mm in length were hydrogen charged within the autoclave and subsequently measured using thermal desorption spectroscopy (TDS). The results show how hydrogen sorption curves can be effectively collected to investigate its dependence on time, temperature and hydrogen pressure, thus enabling, e.g., the deduction of hydrogen diffusion coefficients and hydrogen pre-charging concepts for material testing.

Sign in / Sign up

Export Citation Format

Share Document